Process for the catalytic production of olefin-sulphur dioxide compounds of high molecular weight



I Patented Oct. 20,1942

raocsss roa 'rnc CATALYTIC monuc- TION or omrm-smmm moxnm COM- rormns ormen MOLECULAR wsrcn'r Frederlck'E. Frey, Robert Dewey Snow, and Wal--,ter A. Schulz'e, Bartlesvllle, kla., assignors to Phillips Petroleum'Company,

Bartlesvillc.

Olrla., a corporation of Delaware No Drawing. Original applicationJanuary 28,

1934, Serial N0. 708,520. Renewed June 8, 1938. Divided and thisapplication July 28,1941, Se- I rial No. 404,429

, 7 Claims. (Cl. 260-94) This invention relates to the'manufacture ofcompounds of high molecular weight by the reaction of sulphur dioxidewith unsaturated organic compounds, and comprises processes forcatalytically inducing or accelerating such reactions; all as more fullyhereinafter set forth and as claimed. a

This application is a division of our co-pend-' ing application, SerialNo. 708,520, filed January 26, 1934, renewed June 8, 1938.

The reaction of sulphur dioxide with conjugated dioleflns is well known,and results in two products, one crystalline and one amorphous. The useof anticatalytic compounds, and of high temperatures, has been claimedto favor the exclusive formation of the crystalline modification(Matthews and Strange, U. S. 1,192,259 (1916);

Standinger, Ger, 506,839 (1930) Perkins Can. 329,043 (1933) The reactionof sulphur dioxide with monooleflns was first reported by Matthews andElder (Brit. 11,635, 1914) who formed amorphous products of highmolecular weight by reacting some of the simpler oleflns with sulphurdioxide in the presence of sunlight or other source of actinic light.More recently, Fitch and Frey (application Ser. No. 599,350, filed March16, 1932, now U. S. Patent 2,128,932 granted September 9, 1938) havedescribed and claimed the process of inducing and carrying out thesereactionsin the absence of such source of light, by the useof suitablesubstances which exert a catalytic efiect. Among such substancesspecifically claimed are oxygen and organic peroxides, salts of silverand monovalent copper, and oxides of nitrogen.

,We have found that many other substances will induce and promote thereaction of sulphur dioxide with olefins in the dark. Among suchsubstances are many belonging to 'the following classes.

I Nitrates A. Inorganic (1) Metallic r (2) Nitric acid (3)Ammoniumnitrate (4) Nitrates of amino compounds,

such as NH4NO: 13. Organic a (1) Alkyl, such as CzHsNO; (2) 'Aryl, (3)Nitrates of organic amines C. Ox'ganom'etaIlic', such as phenylmercurlc' nitrate n Nitrltes A. Dilute nitrous aci B. Nitrites of metalandamine com-' pounds a I C. Organic nitrites, alkyl and aryl. IIIPerchlorates IV Chlorates V Dichromates,

VI Chromates VII Persulphates VIII Organometallic compounds,

Mercury alkyls Lead tetraethyl Lead tetraphenyl Triprenylbismuthine IXOzonides of organic compounds such as lid-ixtures of two or moresubstances from the above classes may be used, provided, of course,

that they do not react with each other.

Inasmuch as the reaction between sulphur dioxide and the unsaturatedcompound occurs generally in the liquid phase, the catalytic substancemust either be soluble in the mixture of sulphur dioxide and unsaturatedcompound, or must react with one of its constituents to form an inter.-mediate compound which is soluble in the reaction mixture. For example,silver nitrate, lithium. nitrate, ammonium nitrate, and. dilutealcoholic nitric acid, all of which are somewhat soluble in the reactionmixture, carry the reaction rapidly to completion. On the other hand,barium nitrate, zirconium nitrate, titanium nitrate, strontium nitrateand mercuric nitrate, all

. of which are relatively insoluble in the reaction 'mixture,,do notstart the reaction at once, but

after a period of induction extending over several days, the reactionbegins, and goes to completion at a moderate rate. The fact that thereaction takes place after a period of induction would seem to indicatethe possibility that there has been some chemical reaction between theinsoluble added substance and something in the ole- 'fln-sulphur dixoidemixture to form a soluble catalyst.

The solubility of a catalytic course depend upon the presence of addedmaterials or diluents in the reaction mixture, or upon the relativeproportions of olefin and sulphur dioxide present. Consequently, anaccurate, quantitative comparison of the effectiveness. of variouscatalytic substances is d'fllcult. However, the data in the followingcolumn will indicate the comparative effectiveness of several compoundswhen added in the amount of about 0.5 to 1.0 per substance may of vliquid sulphur dioxide and butene-2.

' Triphenylbismuthi ue:

cent by weight to a mixture of equal volumes of mu 1 I Percentageconversion of butene-Z to reaction product Catalyst Calcium nitrateSodium nitroprusside. Phenyl mercuric nitrate- Mercuric nitrateTetraethyl lead. Mercury diethyl Catalyst Dilute nitric acid Lithiumnitrate. Ammonium nitrate Ethyl nitrite. Beryllium nitrate Potassiumnitrate- Magnesium perr-hlnrafn Perchloric acid Thallium nitrate.

Calcium nitrate Sodium nitroprusslde Triphenylbismuthine Tetraethyl leadMercury diethylm Mercury di-n-butyl Zirconium nitrate.

d nitrate- Cobalt nitrate Isoamyl nitrite um (him-Mm In the absence ofany such substance, the conversion was never at any time appreciable.

We have also found that the soluble nitrates such as those otlithium orammonium, or dilute nitric acid, are equally as effective as silvernitrate, mol formol. Furthermore, they have an advantage in that they donot tend to discolor the product as silver nitrate frequently does, andare not as liable to be precipitated from the rein the electromotiveseries. I

We have i'ound that the reaction products 01' nitric acid and theorganic amines, such as n-butyl' amine, di-n-butyl amine, tri-n-butylamine, benzyl amine, and aniline, have much greater solubility inhydrocarbons, and mixtures or sulphur dioxide with hydrocarbons, thanhave most n etallic salts, and that they are efiective and suitable forthe conduct 01' our process.

action mixture by the presence of metals. higher Other substances havingsuitable catalytic properties, and'fa'vorable solubility in the reactionmixtures, are nitrolic acids, nitrolates, and

pseudonitrols These more soluble catalytic substances are especiallysuitable for use in our process when reacting sulphur dioxide with anunsaturated compound in the presence of inert diluents, such. as paramnhydrocarbons.

The above named substances may be conveniently added to the mixture tobe reacted, in the form of a finely ground solid; or they may be addedin solution in alcohol or otherinert organic solvent, and dispersedthroughout the mixture by shaking or stirring..

The products obtained in our process with the use of these catalyticsubstances are practically identical with those obtained by reacting thesame unsaturated compound with sulphur dioxide in the presenceofsunlight.

Examples of the application of this process are:

I. Equimolecular solutions in absolute ethyl I alcohol were prepared asfollows: Saturated AgNOz, 1.6 g. LiNOs per 100 cc, 1.88 g. NH4NO3 per100 cc. One-half cc of one of the solutions -was added to a tubecontaining approximately g. of a mixture of S02 and butene-2, and the.extent of the reaction was observed at various times after warming toroom temperature and mixing. The data are given in the following table:

Per cent conversion to reaction product I v Time,hours V Catalyst v1&2'2 a 6 9 14 1s A NOL e0 100 .l LiNOs 10 NH4N0| 10 100 II. To amixture or equal volumes of sulphur dioxide and olefins contained in anautoclave or other pressure vessel is addedfrom 0.01 per cent to 0.1 percent, or more, by weight, of one of the substances shown above to exerta catalytic eilect upon the reaction. The catalytic substance isdissolved or dispersed throughout the mixture by thorough stirringor'shaking, and the reaction is allowed to take place at temperatureswithin the range of 25 C. to +4 O C.

, 111. To ,a mixture of equal volumes of allyl 1 alcohol and sulphurdioxide is added 0.5 percent by weight of lithium nitrate. In a fewdays, in

thedark, the 'allyl alcohol is completely 'converted to a solid, whitepolymer.

In the following claims the phrase soluble in the reaction mixture, orequivalent language,'is to be taken as including substances. which areactually soluble in the reaction mixture as well as those whichapparently react with the mixture to form soluble :compounds havingcatalytic properties. I

Having described our invention, what we claim is: 4 v

I. The 1 process of producing high molecular weight heteropolymers ofolefins and sulphur dioxide, which comprises reacting oleflns withsulphur dioxide in the presence of an acid selected from the groupconsisting: of nitric. acid and nitrous acid.

2. The proces s of producing high molecular weight heteropolymers ofolefins and sulphur dioxide, which comprises conducting the reaction inthe absence of light in' the presence or an acid weight heteropolymersof olefins and sulphur dioxide, which comprises reacting oleflns withsulphur dioxide in the presence of nitrous acid.

6. The process oi producing high molecular weight heteropclymers ofoleflns and sulphur dioxide, which comprises reacting olefins withsulphur dioxide in the presence of dilute nitric acid.

7. The process of producing high molecular weight heteropolymers ofoleflns and sulphur diox- 10 ide, which comprises reacting oleflns withsulphur dioxide in the presence of dilute nitrous acid.

WALTER A. SCHULZE. ROBERT DEWEY SNOW.

